LCC & stitching tips please?

[narikin]

Can I pick more experienced brains here - I'm having problems with stitching and LCC:

I thought when an LCC is applied, the color shift and light fall-off in panels of, e.g. a simple 2 way stitch will even out any color imbalances, but it doesn't 100% fix it, and I'm still having to go into C1's Color balance and visually fine-tune each section so they are closer at the point where the images will meet. Is this how it is, or am I missing a trick?

My workflow: make an LCC for each shot as its taken, same aperture, process it as an LCC in C1, (tried both Technical Wide Angle setting on and off) and then apply it to its relevant shot. It sure helps get you in the ballpark, but its not a home run - the left and right half are still slightly different, and need a bit of careful color tweaking to come closer. I do color balance the LCCs to neutral grey in the middle - should I be doing it at the overlap/common edge, or is this immaterial?

(IQ180 + Alpa Max + variety of lenses, usually the new 90mm HR Alpagon + C1 7.1)

thanks

 

[jagsiva]

What version of C1 are you using?

If you are simply creating and applying LCC, I have noticed that sometimes strange things happen. Try saving the LCC as a preset and then applying from the pull down in the LCC tools panel.

 

[Christopher]

For me it just sounds looks like a typical IQ180 Problem. Does it happen with all images or just sometimes ? For me it's not always but often. The P65 had never any similiar Problems. I think it actually relates to the issue that the IQ180 is much more sensetive when it comes to stitching.

 

[narikin]

Jagsiva - Am using C1 Pro 7.1 - the latest version.

Christopher - Yes the IQ180 is far worse for color casts. The P65/IQ160 sensor was much better in this respect, totally agree. And I think, so do Phase. What I don't get is why LCC doesn't fix it like its supposed to?

On top of all this, I'm not even using wide-angle lenses, which make more of a problem with incident angle color casts. The widest Alpa lens I own so far is a 60mm!

 

[jlm]

i would think if you are stitching, that the edge images at their far edges would have the most color cast, and not at the overlap edges with central images. implying that the LCC is over-correcting the edge images

 

[Christopher]

I don't know if I am correct, but I have the feeling the issue is a global one. I mean that the difference in two shots when stiching isn't really the normal Color Cast, which LCC kills perfectly, but that the whole Image (Color and Lumin.) Is different because the light is hitting the Sensor in a different angle. As I don't have the technical infos, it's just a wild guess, but it could be tiny internal relfections in the sensor which produces different images.

And please DON'T give me the Explanation, well 30 seconds have passed between the images and the light changed... My Cannon can do it and my Nikon as well without showing any differences in COLOR.

 

[David Kaufman]

I use an Phase 40+ with an Arca MLine2 and have the same problem all the time. I think neutralizing the LCCs to medium grey is a mistake. In C7.1 simply using the LCC shots and creating LCCs with the menu command is sufficient and will give you better results than taking the added step of neutralizing to grey. But there is no question that there is sufficient variability in the way the program creates LCCs and applies them to their respective photographs in a stitching workflow that small colour discrepancies at the stitching interfaces are created. I find this is true from top to bottom: In a two or three way stitch using vertical components, the bottoms may match after LCC application but not the tops, or vice-versa. The wide-angle option for wide angle lenses works better than C1 v6 did but a lot of fiddling with colour and sometimes density is till required.

 

[danlindberg]

Use custom white balance when stitching. Makes life easier later.

 

[Christopher]

What makes it easier ? I mean what is the benefit ? So far I use daylight and than use the tweaked one.

 

[etrump]

Are your exposures shifted or moving the camera?

 

[Christopher]

In my case: Exposures for example are 10s each, only the back is moved lens stays the same. Still different color in both images, with same C1 settings and LCC applied.

 

[danlindberg]

I have found that auto or daylight white balance produce a small variance between exposures (no matter how fast you are or if light 'seems' constant). Using a fixed Kelvin for the raw makes it easier to develop the same tone in Capture One.

 

[Don Libby]

I have found that auto or daylight white balance produce a small variance between exposures (no matter how fast you are or if light 'seems' constant). Using a fixed Kelvin for the raw makes it easier to develop the same tone in Capture One.

While I normally keep my IQ160 set to auto this makes some sense. Each shot will produce its own white balance if left on auto - no matter how small it might be it may be enough to effect the outcome. I'm on a trip next week and will try to remember this and do a test using both auto and custom.

Don

 

[kdphotography]

I keep the IQ180 WB default set to daylight. It's more consistent and easier to work with later, imho

 

[Don Libby]

I keep the IQ180 WB default set to daylight. It's more consistent and easier to work with later, imho

Not a bad idea for a quick down and dirty hit and run...

 

[narikin]

In theory (...) WB should make no difference in RAW. Once you have applied a set of changes in C1, then that's it, regardless of what was set on the back.

But I will give it a try, as "in theory bumblebees can't fly"

 

[Aviv1887]

Another thing you might like to try (or already do), is to make sure you undo any corrections -like curves, highlights, shadows etc -that might have been applied on your LCC's before you process them. It makes sure you don't "accentuate" any irregularities.

 

[jlm]

white balance in the back is just a convenience (and i use daylight); i always white balance in C1. my thinking is if stitching (or shooting pano's), first apply the specific LCC to each shot, then white balance one of the shots using a neutral element in the image, then copy the same WB to each shifted image

 

[narikin]

white balance in the back is just a convenience (and i use daylight); i always white balance in C1. my thinking is if stitching (or shooting pano's), first apply the specific LCC to each shot, then white balance one of the shots using a neutral element in the image, then copy the same WB to each shifted image

Yep, thats what I do - apply to each its specific LCCs, then adjust the WB of a good example, but if I simply copy that WB across, they are not the same, and do not match - one side of a stitch has different cast than the other, and still needs manual adjustment to get closer.

It's odd, and to me is not what applying an LCC is meant to do - remove angular color shifts.

 

[Pemihan]

I have the exact same issue with my Aptus II 7, I use daylight wb while shooting, but no matter what I have to manually adjust one image before stitching.

Did you ever find a solution?

Peter

Yep, thats what I do - apply to each its specific LCCs, then adjust the WB of a good example, but if I simply copy that WB across, they are not the same, and do not match - one side of a stitch has different cast than the other, and still needs manual adjustment to get closer.

It's odd, and to me is not what applying an LCC is meant to do - remove angular color shifts.